52-year-old Julio Cu Camara dives into the sewage system in Mexico City about four times per month, working anywhere from 30 minutes to six hours to make repairs. His diving suit and helmet weigh more than 80 lbs., protecting him during the dangerous dives. During his 30 years of work, Camara has found dead humans, horses, weapons and car parts, among other things. Mexico City has a drainage system which measures more than 7,456 miles long.